Changes in cell viability and metabolic activity and levels of inflammatory mediators released from H292 bronchial epithelial cells exposed directly to 55 puffs of ENDS aerosol, tobacco cigarette smoke or air (controls)
| Viability (%) | Metabolic activity (%) | (pg/mL×10−7 cells) | ||||||
|---|---|---|---|---|---|---|---|---|
| IL-1β | IL-6 | IL-10 | CXCL1 | CXCL2 | CXCL10 | |||
| (A) Control and reference product | ||||||||
| Air (control) | 78.6±2.7* | (Reference)* | 12.1±2.4* | 10.3±0.5* | 14.5±7.0* | 16.4±6.1* | 17.0±6.2* | 28.3±1.6* |
| Tobacco cigarette | 3.6±2.8† | 32.7±1.8† | 4.0±.0.1† | 2.1±0.3† | 6.7±0.1† | 4.8±0.4† | 5.2±0.1† | 10.6±0.3† |
| (B) ENDS product type | ||||||||
| Disposable | 67.2±4.5* | 82.3±4.8* | 22.2±4.9 | 57.7±52.3† | 12.8±1.2 | 18.4±7.0 | 20.9±8.4 | 23.7±15.2 |
| Rechargable | 61.1±25.6* | 64.6±4.6†* | 88.3±1.8†* | 106.6±27.0†* | 46.6±42.4 | 67.0±17.5†* | 55.6±29.1 | 111.0±118.9 |
| eGo | 17.9±6.6† | 45.1±2.0† | 31.3±0.9 | 23.4±5.3 | 24.5±7.6 | 22.4±2.0 | 26.6±3.5 | 47.6±34.3 |
| Vaporiser | 25.6±7.2† | 61.4±5.1† | 64.9±1.9 | 27.6±6.5† | 54.8±13.8†* | 48.5±1.8† | 59.7±11.4† | 99.7±65.3 |
| ePipe | 32.17±7.1† | 50.1±2.4† | 82.5±0.8 | 66.7±26.3†* | 55.7±12.3†* | 63.6±8.8†* | 68.5±4.5†* | 112.6±80.7 |
| eCigar | 80.1±11.1* | 95.9±5.0* | 13.0±0.9 | 67.1±63.0† | 12.1±0.2 | 11.2±0.1 | 11.6±0.4 | 37.6±2.8 |
| (C) Nicotine carrier | ||||||||
| PG-only | 50.7±21.4†* | 56.2±1.8* | 75.2±5.3† | 21.3±4.6†* | 44.5±25.6† | 40.6±19.0 | 47.1±11.6†* | 105.9±97.2 |
| PG:VG (50/50) | 49.7±5.8†* | 39.4±5.8†* | 57.8±25.2 | 16.9±6.2† | 41.1±14.1† | 32.4±3.1 | 41.7±10.2 | 67.00±45.1 |
| VG-only | 45.5±11.9†* | 42.0±1.7†* | 31.9±0.1 | 15.5±1.3 | 42.3±14.7† | 38.1±13.1 | 37.1±11.3 | 65.0±22.0 |
| (D) Nicotine concentration in ENDS liquid (mg/mL) | ||||||||
| 0 | 75.7±13.1 | 92.3±4.9* | 2.2±0.9 | 10.8±1.5 | 2.1±0.3 | 5.3±1.7 | 4.8±0.8 | 3.8±2.4 |
| 6 | 87.3±5.9* | 81.7±7.1 | 2.1±0.2 | 10.6±2.2 | 2.9±2.0 | 3.2±0.9 | 3.2±0.5† | 3.6±2.2 |
| 12 | 78.7±16.5 | 91.9±2.6* | 1.8±0.1 | 19.7±2.2 | 2.9±2.0 | 3.5±1.1 | 3.6±0.8 | 3.0±1.8 |
| 18 | 91.6±3.9* | 92.2±7.0* | 1.8±0.1†* | 14.6±7.1 | 2.9±1.7 | 2.8±1.0† | 2.9±0.6†* | 3.1±2.0 |
| 24 | 89.7±7.7* | 89.3±8.6* | 2.5±0.1 | 21.9±5.0†* | 2.3±0.3 | 4.2±1.2 | 5.0±0.5 | 4.3±2.7 |
| (E) ENDS battery output voltage (V) | ||||||||
| 3.3 | 63.4±4.4* | 78.1±1.4* | 31.3±0.9 | 23.4±5.3† | 24.5±7.6 | 22.4±2.0 | 26.6±3.5 | 47.6±34.3 |
| 4.0 | 42.3±4.3†* | 55.5±1.3† | 39.6±0.9 | 13.6±1.3 | 43.4±23.4 | 29.0±1.3† | 30.4±1.1 | 64.0±42.8 |
| 4.8 | 11.7±5.9† | 46.2±4.7† | 17.5±0.1†* | 74.9±19.6†* | 218.3±8.2†* | 180.5±51.4†* | 187.3±63.0†* | 337.5±139.2†* |
| (F) Flavours in ENDS liquid | ||||||||
| Tobacco | 63.3±4.4* | 78.1±1.4* | 31.3±0.9 | 23.4±5.3†* | 24.5±7.6 | 22.4±2.0 | 26.6±3.5 | 47.6±34.3 |
| Piña Colada | 64.0±7.8* | 63.8±2.7†* | 25.5±0.3 | 11.3±5.0 | 26.7±3.8 | 27.0±4.5 | 27.7±5.7 | 48.7±22.4 |
| Menthol | 57.2±10.4†* | 48.5±5.6† | 16.4±0.1 | 14.3±6.6 | 35.5±30.6 | 21.7±2.3 | 26.1±2.2 | 34.4±13.3 |
| Coffee | 44.3±15.5†* | 55.8±2.1†* | 78.1±3.3 | 40.7±9.9†* | 59.8±27.4 | 52.7±18.0†* | 56.0±14.1†* | 124.3±103.0 |
| Strawberry | 12.2±4.6† | 46.2±1.9† | 135±2.8†* | 15.2±12.8 | 125.0±11.3†* | 117.5±14.8†* | 127.3±22.4†* | 226.8±121.0†* |
Statistically significant values are shown in bold.
Mean values for cytotoxicity and cytokine assays. Values are mean±SEM.
*Significant difference as compared to tobacco cigarettes (p<0.05; Kruskal-Wallis test).
†Significant difference as compared to air controls (p<0.05; Kruskal-Wallis test).
ENDS, electronic nicotine delivery systems; IL, interleukin; PG, propylene glycol; VG, vegetable glycerin.